In this lesson,
we're going to cover other network service ports and protocols.
Now, as we talk about other network service ports
and protocols, these are the different network service ports
and protocols that play a pivotal role
in our network time synchronization and the establishment
of communication sessions, as well as directory services.
They're going to be crucial for organizing
and providing access to our distributed information
located all across our network.
To do this, we're going to be looking at three main protocols,
the Network Time Protocol, the Session Initiation Protocol,
and the Lightweight Directory Access Protocol.
Now, first we have NTP or the Network Time Protocol.
Now, NTP is going to be used to synchronize the clocks
of a computer over a given network.
Now, time synchronization may not seem like it's a big deal,
but it actually is vital in our networks to ensure
that the time dependent processes
and the times stamping of events are consistent
across all of our devices.
NTP will operate primarily over Port 123
using the user datagram protocol.
NTP enables our networks to maintain accurate time
with precision and reliability, which is crucial
for transaction logging, security protocols,
and the coordination of system functions.
For example, if your time is out of sync by too much,
your domain controller won't let that workstation
log onto the domain
because it's going to see that there's an issue
between the time of the server and the time of the client,
and it'll actually affect some of your encryption
and decryption functions too,
which is why NTP is so important.
Second, we have SIP or the Session Initiation Protocol.
Now, SIP is widely used for initiating, maintaining,
and terminating real-time sessions that involve voice,
video, messaging, and other communication services.
Most commonly, you're going to see SIP is used
for communication services like voiceover IP applications
that allow you to make phone calls over the internet.
Now, the session initiation protocol can utilize
multiple ports, but traditionally it's going to operate
over Port 5060 on both UDP
and TCP for unencrypted signaling,
and it's going to use Port 5061 using TCP
for encrypted signaling with TLS
or the transport layer security.
The third one we have is what's known as LDAP
or the Lightweight Directory Access Protocol.
Now, the lightweight Directory Access Protocol is actually
a protocol for accessing
and maintaining distributed directory information services
over an IP network.
LDAP is used to look up information in a directory listing,
and it's commonly used in email programs
to find out personal information,
like a person's email address, their phone number,
the department they're in inside of the company,
and things like that from your internal company servers.
When you use LDAP,
it's going to communicate over Port 389 using both TCP and UDP.
Now, unfortunately, LDAP is insecure
and it transmits all that information in plain text.
To overcome this, we have created something known as LDAPS
or LDAP over SSL.
Now, LDAPS is going to be a version of LDAP
that's encrypted with SSL
or in newer versions, TLS for increased security.
You should use LDAPS or LDAPS anytime that you have
a connection that needs to be protected,
due to the sensitive nature of the data being accessed
and manipulated, essentially LDAPS is going to run
over Port 636 using TCP,
and this ensures that the data exchange
during the LDAP sessions is being securely encrypted
before it's sent from the server to a client
or from a client to a server.
So remember, each of these different network service ports
and protocols is going to provide us
with some essential services that support the complex needs
of our modern networks.
When we're dealing with NTP, we're dealing with
the network time protocol that's being used
to ensure all devices on a network agree on the time
and this is really important
inside of our large scale networks.
NTP is going to operate over Port 123.
The next one you need to remember is SIP,
or the Session Initiation Protocol,
which operates over reports 5060 and 5061,
and SIP is going to be used in various forms
of communication over the internet,
including voiceover IP services.
The final one you need to remember is LDAP and LDAPS.
LDAP is the insecure version that provides
directory services and allows for the retrieval
and management of relevant information across the network
using Port 389.
When we want security, we're going to use LDAPS
or LDAPS over Port 636,
which provides secure directory service transactions
that protects your sensitive data during the transmission
by placing it inside of an encrypted tunnel.